Backups Last line of defense against disaster
Relatively inexpensive solution with
low data currency
Quickly roll back transactions if data
100% local protection
Staged backups and batch
Disaster tolerance, with varying
Remote mirrors degrees of data currency and
Snapshots are fairly inexpensive but it’s a point in time copy. Quick rollback
from data corruption but no protection against primary logical unit failure.
Split mirrors – 100% copy of local data. Quick rollback from data corruption
and protection against primary logical unit failure. But we can’t hold as many
splits as we can snapshots because it takes up the same amount of disk
capacity as the original volume.
Neither of these protect against subsystem failure or site failure.
So here we probably want to use it in conjunction with remote mirrors
A lot of the time we are probably going to use in-system replication and remote
replication at the same time so we will have multiple copies of our data.